Circuit breaker and ignition timing device



Oct. 2, 1945. v w QcHSEN BE|N I 2386,1 36

CIRCUIT BREAKER AND IGNITION TIMING DEVICE Filed April 21, 1942 27 I I 23b 25 25 a2- 22 5 E WALTER oa/szws/y J INVENTOR- m 26 25a. I BY I ed/1 ATTORNEY Patented Oct. 2, 1945 V srrAr E's PATENT cmcurrl aEAKEmANnuGNIimon TIMING Device Walter Ochsenbein, Bern, Switzerland? assignor to Hasler" AwG. Werkefii'w Telephonie und Erfizisionsmechanik, Bern, Switzerland Aippiication'A pril 21, 1942; oria1..-No.4a9,s7&=

In-Switzerland Januarsz,3,1194j1 I 8 Claims; (01. 1 23-11 1 The present-inventionrelates to acircuitbreakconduit. [4 leadsito a hydraulically oplated'rder er andigm'tion timihg-dev-iceforinternalcombusvi'cef for adjusting the spark timing. tion enginesa the. drawing-,vthis device is shown by way One -object of the present'inventiorr is"to"pro"- of. example. as aihyd'raulic brake acting on a vide meanswherebythecircuitbreaker contacts 5 portion of. the magneto coupling. 22; Thelatter of" a normally cam operated circuit breaker decomprises. a cuprlike, coupling portion. 2.3 keyed vice are movedtoand retained=in apermanentto-the shaft 24 ofamultiple magneto (not shown). lyopen position independently of the cam action The second couplinglportion 25 is formedasa whenever the rotary speed of themagneto procoverandrotatablyseated with its hub 25a.up'on duces a sufficiently high voltage-in-thesecondthe. hubfl23'aiofi the. portion. 23. Both portions ary circuit ofithe circuit breaker topermit-gen- 23.ancL 25,t,ogether form a housingtfor a spiral oration of an ignition spark without alternate SD g theimlelv -L which isconnected opening and closing= of 'the' primary circuit; to theuhub 25avofthe coupling portiont25 while Anotherobject-of the invention'istopre'serve outer end s secured to the inne pe phe al the frictionally cooperating surfaoes of the breakwalllsurfaceof the coupling por i0n=23-by1 m ns er: contacts and of the control cam; respectively, ofga. rivet 250. The cylindrical; flange of. the byrthe provision of means for lifting-the-breaker up portionl3pisrpmvidedwith upstanding contacts entirely 01% the control cam; when the DIOJ DS- Nid the p po b 25 voltageproducedby themagnetoin the secondary riesiradiallprojec'tions 25b meshing, with s me circuitor the circuit breakerissufiicientlv high play with the p 0ie s231i t at t tw -0 roi: thegeneration of ignition' sparhs-withoutinpli'neporti nscan nsul ly p ac r l' iv termittentaclosing-of the primary circuit. to each. other. tofla predeterminedextent. Nor,-

Arstill further object of=theinvention is to-proa liit ey are u e y t Spring n a vide; in" combination with a circuit breaker of position in whiohtthereari surface of each pr the type mentioned; means to readjust the timing tiOn 1) c n s t e front-Surface O ee ofrthe sparking device automatically upon setfollowing, projection 23b. A gear wheel 21 is' tingsofithe breaker contacts to their permanently Scure by means of screws, 28' to brackets 25 openpositions soas to compensate forthe more g a t ep g P n- Said gear rapid generationoffthe sparking voltage obtained W e b g adapt d be gear d a a Sui in this manner. ratiohto, the crankshaftof the engine.

These and other objects which-will appear more When the geali Wheel is-rotated 510W e clearlyl asthe description proceeds; areaccomgiile p the upling-p n 23 i d plishediby the arrangement and combination of relativeto.thecouplihg.portion25 by the attract elements. setzforth' in the-following detailed detion of .the multipole magneto and, the tension scription, defined in the. appended claim and 5 of vthe. spring 261 is-v increased until the portion illustrativelyexemplified-in the appendedidrawpositively advanced y e front ce ing; the single figure of which shows partly" in of'each projectioni25bl acting upon the rear sure elevation and partly in section-a circuit breaker a e I. ?t en xtip p e n k A arrangement according. to the invention including hi h Bfi el p e t e ma neto att act on 108- means for a readjustment of the spark timing. Comes relat ve y n gible and the sprin 26 A lever. 4zisamounted rotatablyon'theshaft-1 tends to hold the portion 23.permanently in its ofa cam disc 3 which controls two circuit breaker o i inal positionr l tive t t e o p in p rti levers. 2. Lever 4 carries-atitsendstwo lateral- 2.5lwhi'ofi pos t o fl' 'e ponds to anearly Sp ly projectingbosses'5::andisconnectedby arod mi ato a piston Twhichisslidable in alcylinder-y8 h order to produ e a l e niti t n ine andxurgediupwardszinsaid cylinder by a spring Spe s e ce a predetermined m gni d t 9g, Thespace i theucylinderza aboveuthe piston brake 21' is operated. This. brakecomprisesa 1 communicates through a conduit I0 with an b a ehe t p d n of t e outer operator controlled three way valve: H to' which flange 'the coupling portion 3 by '--p areconnectedairetumconduit l2leadingtman fitted slidably in a cylinder 32 andheld. by: a oil tank; In the illustrated position of valve pring 33 normally in a Position n Which t e [l the oiLpump is connected tothe conduitsr Ill b a e is inoperative.v The brake cylinder 32 is and, I4; The valve Il may; be turned; thr h provided with a port 34' connectedto the .conduit :3-in azclockwisetdirection tonconnectitheconthe admission Ofoil in the a the duits, wand... tothereturnmoncluit l2 The ,5. p StOnB] to cause axiaidispla nt i lat- 6 by a spring 20.

When the engine is at rest, rod 6 with piston 1 is in its upper end position so that the bosses 5 of lever 4 do not interfere with the movement 7 of the circuit-breaker-levers 2 which are then controlled by the cam disk 3. -When the speed a of the motor has reached a certain value, rod 6 with cam I 8 is pressed downwards by apressure on the piston 1 depending upon the num-' ber of revolutions of the engine. Cam l8 touches with its lower bevel edge the bevel edge of follower head l9. The inclination of said bevel edges of cam 18 and of head l9 and the tension of the adjustable spring are so chosen, that rod 6 removes'rod l'l only at a certain value of the pressure on piston I the follower head 19 is caused to ride up the entire bevel surface of cam l8. As soon, however, as this pressure value is exceeded and the tip of follower head I9 rests against the surface of cam l8 extending parallel to the longitudinal axis of rod 6', th resistance of the follower l9 against the downward travel of cam l8 and rod 6 drops suddenly almost to zero and the rod 6 is jerked downwards against the action of spring" 9 into its lower end position which is defined'by the contact of piston 1 with a shoulder 8' of cylinder 8. By this sudden downwards movement of rod 6, lever 4 is shifted abruptly from its inoperative'position, and the bosses 5 push the circuit breaker levers 2 instantly out of the path of cam disk 3. A sufiiciently high sparking voltage is reached without operation of'the circuit breaker at the high speed of the engine producing the predetermined oil pressure value, and the sparking will, thus, be continued after the sudden cutting out of the circuit breaking levers. 'When the follower head is displaced towardthe'right, the rod l1 turns the valve I5 by means of theleverage l6, and, at the precise moment when the rod 6 is jerked downwardly,

cam disc, a rookable lever capable of assuming an operative position in which a cam portion of said lever cooperates with said breaker contact to hold the same in a permanently open position beyond the reach of said cam disc and an inoperative position in which the lever does not interfere with the control action of the cam disc on the breaker contact, means urging said lever towards said inoperative position, and means for moving said lever from said inoperative to said operative position when the engine speed reaches the Value at which an intermittent opening and closingof the circuit breaker is no longer required for the generation of a sparking voltage.

2. A circuit breaker arrangement, asclaimed in claim 1, in which said lever is rookable about the axis of rotationof said cam disc.

3. A circuit breaker arrangement, as claimed in claim 1, in which said means for moving said the valve [5 has assumed its open position so that the oil under pressure can flow into the brake cylinder 32 and cause the brake to act on the coupling portion 23. The latter will thus be angularly displaced from its position with respect to the coupling portion 25 into which it is urged by the spring 26. This angular displacement, in turn, effects a retardation of the ignition compensating for the more rapid generation of sparking voltage in the magneto by the free development of the magnetic field as compared to. its operation with an alternately open and closed circuit breaker.

If; for any reason it should be desirable at a high engine speed to have the circuit breakers operate, cock H is turned from the shown position clockwise through 90 whereupon the oil will be pressed by the piston 1 under the efiect of spring 9 from cylinder 8 into the oil tank and 'lever 4 is swung back by rod 6 to free circuit breaker levers.

What I claim is:

1. A circuit breaker arrangement for the ignition mechanism of an internal combustion engine, comprising in combination with a cam' disc and at least one normally closed, breaker contact arranged to'be'intermittently opened by said lever includes a first cam displaceable in one direction in dependence upon a force which is a function of the engine speed, said cam having a bevelled nose portion and rearwardly of said nose portion aface extending substantially parallel to the direction of its movement, a second bevelled cam displaceable in a direction at substantially right angles to the direction of movementof said first cam, and a spring urging said second cam against said first cam.

H 4. A circuit breaker arrangement, as claimed in claim 1, including means operative when the engine speed reaches said value to retard the spark timing so as to compensate for the mor rapid generation of sparking voltage.

7 5. In an internal combustion engine having an engine driven oil pump and an ignition mechanism including a circuit breaker containing an engine driven cam disc and at least one normally closed breaker contact arranged to be intermittently opened by said cam disc, the combination of a rookable lever capable of assuming an operative position in which acam portion of said lever cooperates with said breaker contact to hold the same in a permanently open position beyond the reachof said camdisc and an inoperative position in which the lever does not interfere with the control action of the cam disc on the breaker contact, a closed cylinder having a lower part and a head portion, a conductorconnecting the head portion of said cylinder with said oil pump, a piston slidable in said lower part'of said cylinder, a spring in said cylinder below said piston to urge the latter towards the head portion of said cylinder, and a piston rod extending through the bottom of said cylinder and having its free end hinged to said lever, so as to move the latter from its inoperative to its operative position when the oil pressure acting on said piston reaches a value corresponding to the engine speed at which an intermittent opening and closing of the circuit breaker is no longer required for the generation of a sparking voltage. 6. In a combination, as claimed in claim 5, an oil outletoonduit and operator controlled means for disconnecting said. cylinder head portion from said oil pump and connecting it to said oil outlet conduit.

7. In a combination, as claimed in claim 5, a hydraulically operated mechanism for retarding the spark timing, a conduit connecting said mechanism with said oil pump, a normally closed valve in said conduit ,-and means for opening said valvewhenthe engine speed reaches said value.

8; In an internal combustion engine having an engine driven oil pump and an ignition mechanism including a hydraulically operated device for retarding the spark timing and a circuit breaker containing an engine driven cam disc and at least one normally closed breaker contact arranged to be intermittently opened by said cam disc, the combination of a rockable lever capable of assuming an operative position in which a cam portion of said lever cooperates with said breaker contact to hold the same in a permanently open position beyond the reach of said cam disc and an inoperative position in which the lever does not interfere with the control action of the cam disc on the breaker contact, a closed cylinder having a lower part and a head portion, a conductor connecting the head portion of said cylinder with said oil pump, a piston slidable in said lower part of said cylinder, a spring in said cylinder below said piston to urge the latter towards the head portion of said cylinder, a piston rod extending through the bottom of said cylinder and having its free end hinged to said lever to hold the latter in its inoperative position as long as said piston is near its upper position in said cylinder and to move the lever from its inoperative to its operative position when the piston is displaced under the oil pressure to its lowermost position in said cylinder, a conduit connecting the spark timing retarding device with said oil pump, a valve in said conduit, a valve rod displaceable along its own longitudinal axis in a direction at right angles to the direction of movement of said piston rod, a first cam on said piston. rod, said first cam having a bevelled nose portion and, rearwardly of said nose portion, a face extending substantially parallel to the movement of said piston rod, a second bevelled cam on the free end of said valve rod and a valve rod Spring holding said valve rod normally in a position in which said second cam extends into the path of said first cam and said valve is closed, the bevel surfaces of said cams the power of said'valve rod spring and the connection between said valve rod and valve being so chosen and arranged that the oil pressure on said piston acts on the cooperating bevelled cam faces to shift the second cam out of the path of the first cam at the exact moment when the oil pressure reaches a value corresponding to the engine speed at which an intermittent opening and closing of the circuit breaker is no longer required for the generation of a sparking voltage, and said valve is opened by said valve rod at precisely the same moment, whereby the lever is shifted abruptly to its operative position and simultaneously the spark timing is sufficiently retarded to compensate for the more rapid generation of the sparking voltage. WALTER OCHSENBEIN. 

